Java Large Memory Heap Size

[Amit Dixit_2]

Hi,
We are running HP-UX B-11.11 PA-RISC
and HP-JVM 1.4.2
We recently installed patches, so that we can upgrade the heap size from 2 gb to 4gb.

But when I change the heap size setting in the startup script of the server -Xmx and Xmn the server doesn't get started and generates the following error message

/usr/lib/dld.sl: Call to mmap() failed - TEXT /opt/java1.4/jre/lib/PA_RISC2.0/native_threads/libhpi.sl
HPI dlopen failed: Exec format error

Does anyone know what is the problem.

Thaks,
Amit.

[Steven E. Protter]

Are you running the 32 bit OS or the 64 bit OS.

If you are 32, that might explain the trouble. Address limits. Think about memory windows.

SEP

[Steve Steel]

Hi

It is always address space and memory windows is needed

see
ftp://eh:spear9@hprc.external.hp.com/memory.htm#memory_windows


For memory windows details

You are running out of space


Steve Steel

[Amit Dixit_2]

Hi,
We are running 64 bit O.S., so it should support this memory issue. And to have HP-JVM 1.4.2 up and running with this large memory heap we installed the required patches still I am getting this error.

[Don Morris_1]

The OS is 64-bit, but if the application is 32-bit, you're still limited to a 4Gb address space, of which 2Gb is by default globally shared. If you want >2Gb private space, you must use chatr (or I think there's a linker option - but obviously you won't want to relink java) to use Q3 and/or Q4 private. This will get very interesting if you want a 4Gb heap *and* need to load shared libraries (i.e. you won't be able to do it... I'd expect a 3Gb heap at best for an app like Java, since I also expect it to heavily use system shared libraries). More details on address space layout, etc. are in the Memory Management whitepaper (http://docs.hp.com/en/1218/mem_mgt.html).

You'll also need to set maxdsiz / maxdsiz_64bit to 4Gb, if Java literally uses heap and not MAP_PRIVATE mmap's.

[RAC_1]

You will have to tune your setting for maxtsiz_64bit. How much RAM do you have??

Also be up to date on Java patches.
hp.com/go/java

Also, just eager to know, why you need so much heap size??

Anil